Taxonomic confirmation of mud crab species (genus Scylla) in Bangladesh by nuclear and mitochondrial DNA markers

Abstract

Taxonomy of mud crabs genus Scylla has been misidentified for several years due to their high morphological plasticity. Several reports concerning mud crab have been published with misleading identification in Bangladesh. In this study, partial fragments of nuclear and mitochondrial DNA of Scylla species obtained from four locations along the Bangladesh coast were used to resolve taxonomical ambiguity of mud crab species. A single PCR product from the nuclear first internal transcribed spacer (ITS-1) marker and phylogenetic trees constructed based on 16S rDNA sequences indicated that all Scylla species obtained in this study were S. olivacea. Both molecular data and morphological characters revealed that S. olivacea is the only major species in Bangladesh coastal waters. Further, the 16S rDNA haplotypes significantly differed with known S. serrata by 33%. From this study it is clear that ‘S. serrata’ commonly reported from Bangladesh should be S. olivacea.

Keywords:

• Internal transcribed spacer
• 16S rDNA
• mud crab
• taxonomy
• phylogeny

Acknowledgements

We thank Satchidananda Biswas Satu for assistance with live mud crab sample collection and Partho Pratim Debnath for help with DNA extraction in Bangladesh.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Funding

This work was supported by Japan Society for the Promotion of Science (JSPS) Grants. MG Sarower acknowledges research fellowship support from the JSPS.